Non-binary LDPC code decoder

Abstract

The present disclosure relates generally to data decoding, and more particularly to non-binary iterative decoders. Non-binary LDPC codes and LDPC decoders that may be used to decode non-binary LDPC codes are disclosed. Systems and methods are also disclosed that compute messages related to non-binary LDPC codes, in a LLRV form and in a metric vector form and to process these messages in non-binary LDPC decoders. Systems and methods are additionally disclosed that convert messages between the LLRV form and the metric vector form. The implementation and use of non-binary low density parity check code decoders, the computation of messages in the LLRV and metric vector forms, and the use of message conversion systems and methods, according to this disclosure, may provide increased information relating groups of codeword bits, increased computational efficiency, and improved application performance.

What is claimed is: 
     
       1. A method for decoding, using a non-binary decoder, a vector received from a communications channel, the method comprising:
 determining soft information based on the received vector using a detector; 
 computing a plurality of messages based on the determined soft information, wherein each of the plurality of messages are in one of a first form and a second form; and 
 converting at least one of the plurality of messages from the one of the first form and the second form to the other of the first form and the second form using format converter circuitry to thereby decode the received vector, wherein one of the first form and the second form includes a most likely non-binary variable value and values relative to a most likely variable likelihood value, wherein both the first form and the second form include non-binary variable likelihood values. 
 
     
     
       2. The method of  claim 1 , wherein the first form is a metric vector form and the second form is a log-likelihood-ratio vector (LLRV) form. 
     
     
       3. The method of  claim 1 , wherein the one of the first form and second form relates non-binary variable values to variable likelihood values that are relative to a most likely of the non-binary variable values. 
     
     
       4. The method of  claim 1 , wherein the converting is based on a comparison operation being performed on at least two of the plurality of messages. 
     
     
       5. The method of  claim 1 , wherein the converting is based on an arithmetic operation being performed on at least one of the plurality of messages. 
     
     
       6. The method of  claim 1 , wherein the soft information relates non-binary variable values to variable likelihood values. 
     
     
       7. The method of  claim 1 , wherein the soft information is in one of the first form and the second form. 
     
     
       8. The method of  claim 1  wherein the computing comprises processing the soft information and the plurality of messages using a layered decoding approach. 
     
     
       9. The method of  claim 1 , wherein the received vector comprises non-binary variables chosen from elements of a Galois field. 
     
     
       10. The method of  claim 1  wherein the non-binary decoder is a non-binary low-density parity check code (LDPC) decoder. 
     
     
       11. A device for decoding a vector received from a communications channel, the device comprising:
 a detector configured to determine soft information based on the received vector; 
 a non-binary decoder configured to compute a plurality of messages based on the determined soft information, wherein each of the plurality of messages are in one of a first form and a second form; and 
 a format converter configured to convert at least one of the plurality of messages from the one of the first form and the second form to the other of the first form and the second form to thereby decode the received vector, wherein one of the first form and the second form includes a most likely non-binary variable value and values relative to a most likely variable likelihood value, wherein both the first form and the second form include non-binary variable likelihood values. 
 
     
     
       12. The device of  claim 11 , wherein the first form is a metric vector form and the second form is a log-likelihood-ratio vector (LLRV) form. 
     
     
       13. The device of  claim 11  wherein the one of the first form and second form relates non-binary variable values to variable likelihood values that are relative to a most likely of the non-binary variable values. 
     
     
       14. The device of  claim 11 , wherein the format converter is further configured to convert based on a comparison operation being performed on at least two of the plurality of messages. 
     
     
       15. The device of  claim 11 , wherein the format converter is further configured to convert based on an arithmetic operation being performed on at least one of the plurality of messages. 
     
     
       16. The device of  claim 11 , wherein the soft information relates non-binary variable values to variable likelihood values. 
     
     
       17. The device of  claim 11 , wherein the soft information is in one of the first form and the second form. 
     
     
       18. The device of  claim 11 , wherein the non-binary decoder is further configured to process the soft information and the plurality of messages using a layered decoding approach. 
     
     
       19. The device of  claim 11 , wherein the received vector comprises non-binary variables chosen from elements of a Galois field. 
     
     
       20. The device of  claim 11 , wherein the non-binary decoder is a non-binary low-density parity check code (LDPC) decoder.